Recently, an optical lens system including pieces of lenses each with a positive (+) refractive power and pieces of lenses each with a negative (−) refractive power is widely used on electronic products. Particularly, with reference to an image pick-up system, a camera module for communication terminal, a DSC (Digital Still Camera), a camcorder, and a PC camera (imaging device attached to a personal computer) include an optical lens system.
The optical lens system is formed by being arranged with a plurality of lenses including lenses each with a positive (+) refractive power and pieces of lenses each with a negative (−) refractive power, as an important factor for obtaining a image of an object. Currently, the lenses are convexly or concavely formed on a spherical surface lens shape or an aspherical surface lens shape to realize a lens shape having a positive (+) refractive power and a lens shape having a negative (−) refractive power.